Strain the rice through a rice colander.
Take the same pot, put some butter in the bottom of the pot and put gazmakh or lavash. I will explain how you can do gazmakh in another recipe. You can also use potatoes instead of gazmakh or lavash. Add the parboiled rice into the pot. Put several knobs of butter on top. Make holes in the rice with the handle of a wooden spoon to allow the steam to escape. Place a well-fitting lid on top of the pot, covered underneath with a clean tea towel. The towel helps to absorb the steam. Set the cooker on the lowest flame. After 5-10 minutes open the pot, put remaining butter on the rice, pour saffron extract and place the lid again on the pot.
Continue steaming of the rice for 45-60 minutes. Plov is ready, when the rice is stuck out.